The wings of an aircraft are typically constructed from ribs, spars and skin panels (e.g., an upper skin panel and a lower skin panel). Specifically, the ribs are spaced apart from each other along the length of the wing. The forward ends of the ribs are connected to the forward spar, while the aft ends of the ribs are connected to the aft spar. The upper skin panel is connected to the upper portion of each rib, while the lower skin panel is connected to the lower portion of each rib. Therefore, the ribs, the spars and the skin panels define an enclosed wing box, which is commonly used as a fuel tank on passenger and commercial aircraft.
When jet fuel is stored within the wing box, the connections between the skin panels and the ribs must be fluid-tight. Traditionally, the process of fastening skin panels to the ribs to achieve a fluid-tight connection requires personnel to enter and work within the confined space of the wing box. Therefore, various safety precautions must be taken, which increases the overall cost of aircraft manufacture. It would be advantageous to assemble the wing box without the need for entering the wing box.
The wings of certain fighter aircraft are assembled by externally connecting skin panels to the ribs, thereby avoiding the confined space issues associated with personnel enter the wing box. However, to meet battle damage requirements, the fuel on fighter aircraft is typically contained within compartmentalized bladders, rather than by the wing box itself. Therefore, fluid-tightness is less of a concern when externally fastening the skin panels to the ribs on fighter aircraft.
Accordingly, those skilled in the art continue with research and development efforts in the field of aircraft wing assembly.